1. The Field of the Invention
The present invention relates to a method of waterproof and floor construction by using thixotropic urethane, in which a thixotropic high viscosity urethane is applied onto fiber sheets formed of fiber materials as a base fixing material before forming an upper coating layer with super high speed hardening type resin, so that generation of pinholes in the upper coating layer can be prevented, a path for humidity induction and a superior reactivity can be provided in case of retraction and expansion of a structure caused by atmospheric temperature difference and vibration, and permeation of humidity into cracks of the structure can be prevented, thereby maximizing stability of waterproof and floor structure.
2. The Relevant Technology
In general, waterproof, corrosion proof, and floor material coating films are on roofs and outer walls of various buildings, tunnels, basements, floors of parking lots, insides of water treating boxes and the like formed according to the purpose thereof. That is, a corrosion proof coating film is formed on a ship or an iron frame, and a coating film of high strength and high durability is formed on the floor of the parking lot or the floor of an industrial facility.
Such the waterproof, corrosion-proof or floor coating film has to be sufficiently adhered to a base layer to secure water tightness, and is imparted with flexibility and behavior reaction property to sufficiently stand impact or vibration transmitted from the outside and volume deformation caused by temperature difference between winter and summer seasons.
As for the waterproof and floor construction, polyurea resin is directly sprayed onto a concrete surface in general. The polyurea resin is superior in the anti-corrosiveness and chemical resistance and forms an elastic and smooth film. If a spraying angle thereof is controlled, embossing may be formed on the surface to promote the slippage-proof and appearance-improving effect. Further, the polyurea resin has an advantage that the reaction speed and curing speed thereof are very fast so that the polyurea resin is widely utilized for the purpose of forming the waterproof and floor construction.
The polyurea resin has, however, a disadvantage that the water tightness of the concrete is not good when the polyurea resin is directly sprayed onto the concrete, so that pinholes are generated and the surface becomes uneven. Therefore, in order to overcome the generation of the pinholes, a non-woven fabric or an asphalt sheet is utilized to wrap the concrete surface before applying the polyurea resin. However, this is also a complicated work and results in the bad walking feeling in the case of roof waterproofing because of the non-woven fabric or the asphalt sheet.
Further, when reinforcing the waterproof layer with the non-woven fabric, the surface of the non-woven fabric may become rough owing to a coating film applied to the non-woven fabric, and moisture of the coating film or paint may be absorbed into the non-woven fabric in a short time, resulting in the deterioration of the construction thereof. In addition, it is very difficult to form a hole in the non-woven fabric to pass coating materials owing to the own properties of the non-woven fabric, so that it becomes difficult to form an insulating or partial insulating waterproof structure. Therefore, reaction property to the behavior of the base element becomes deteriorated so that the reaction to the cracks or humidity of the base element becomes decreased.
Korean Patent Laying-Open Publication No 2006-14901 as filed on Feb. 16, 2006 discloses “a method for waterproof coating by using polyurea resin and a surface controlling material”, wherein polyurethane resin having a low hardening time is utilized as the surface controlling material. The method as disclosed in the Korean Patent Laying-Open Publication No 2006-14901 includes the steps of removing impurities from a surface of a base element, applying a primer first onto the surface of the base element, applying the surface controlling material onto the primer by a predetermined thickness, applying the primer secondarily, and applying polyurea resin. The prior art method utilizes the property of the polyurethane, which is slow in hardening and has self-leveling function. The self-leveling function makes a flat surface controlling material layer formed by the fluidity of the polyurethane, wherein the polyurethane has viscosity in a predetermined range to secure the fluidity.
The prior art waterproof coating method has, however, a disadvantage that it is impossible to apply the polyurethane resin used as the surface controlling material to a construction surface when the construction surface is wet (the present inventors' Korean Patent No. 565908 published on Mar. 31, 2006). In the prior art method, all of the primer, the surface controlling material and the polyurea are applied on the entire surface of a waterproof base surface, so that the reaction to the behavior of the base surface becomes decreased, resulting in the loosening of the waterproof base layer or generation of cracks.
Korean Patent No. 565908 discloses a waterproof construction method, which includes the steps of removing impurities from a surface of a base element by using a mixture of an aqueous polymer composition consisting of cement as the surface controlling material, a dispersing agent, inorganic powder composed of mineral based inorganic substances, water soluble emulsion acryl, water and stabilizer, spraying water on the base element from which the impurities are removed to make the base element wet, removing water staying on the surface of the base element before 20-30 minutes from applying the surface controlling material, applying the surface controlling material onto the surface of the base element, applying a primer onto the base element, and applying polyurea resin onto the base element.
This prior art method has an advantage that the waterproof construction may be achieved when the base surface is wet as well as the base surface is dry. However, the prior art method still has disadvantages that working procedure thereof becomes complicated owing to the repetition of the wet and dry states and that the humidity of the base concrete element is not properly discharged, deteriorating the properties of the waterproof layer. Further, the waterproof material including the surface controlling material is applied on the entire surface of the base element so that the waterproof material cannot react to the behavior of the base surface.
Korean Patent No. 408010 discloses a waterproof construction method using polyurea, wherein a non-woven fabric serving as a reinforcement element is fixed to a waterproof base surface by nails or washers before spraying and coating the polyurea. This prior art method has, however, disadvantages that the fixing elements such as the nails or the washers may damage the waterproof structure and are apt to be corroded by the humidity introduced via defect portions, weakening water tightness of the entire waterproof structure.